Bridgestone Motorcycle Parts Discussion Board

Bridgestone Tech Talk => Engine => Topic started by: stingray68 on August 08, 2017, 09:06:43 AM

Title: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on August 08, 2017, 09:06:43 AM
Hello Everyone,

   I would like to remove the carb and give it a good soak and cleaning, but I don't see anywhere in the manual that explains how to remove the choke cable from the carb.  I loosen the nut and it just seems like it binds up and never wants to disconnect from the carb.  Am I doing something incredibly wrong or making this much harder than it really is?  I would not doubt either one is very possible!!!  You all have been such a great help with this project and I am getting close to getting this bike on the road again.  Thank you all in advance.  Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: mqtsteve on August 08, 2017, 09:20:56 AM
Mike,
You're right it's simple!  Spray penetrating oil in the hole and let it soak.  The plunger just pulls out as long as the cap nut and adjuster are free.  It took a couple of days of soaking before I could remove one of mine.  Good luck, Steve 
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: BRT-GTR on August 09, 2017, 07:03:48 PM
       If it won't budge after a good soak, disconnect the cable at the lever end and slide the outer cable up so you can get at the choke plunger. Use a small screwdriver in the cable slot to give it a gentle twist. Usually does the trick.
        Brian.
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on August 28, 2017, 10:58:47 AM
Hi Guys,

   Well after a good long soak and a little twist of the screw driver the plunger is now free! I do now have another issue.  The cable will not stay connected to the plunger.  I am afraid that I may have widened the slot with the screw driver.  I was wondering if anyone has had to modify the plunger and cable connection or do I need to replace the cable at this point?  Thank you all in advance for the help....Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: BRT-GTR on August 28, 2017, 01:56:35 PM
           I assume the nipple is still on the end of the cable. If so, sounds like you may have spread the slot. Just try gently squeezing it back together with pliers or a small vice, the key word being 'gently'. Carefully clean any marks off the plunger with a small file before trying it back in the carb otherwise it could jam again. They are a close fit.
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on August 28, 2017, 02:42:16 PM
Sounds like a great way to fix it, and yes the nipple is still on the end of the cable.  The plunger moves freely inside the carb, but it does not come out of the carb.  Is there an easy trick to getting this out of the carb?  Thank you again, Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: BRT-GTR on August 28, 2017, 03:30:29 PM
          There may be a bit of corrosion at the top of the plunger hole. Don't use anything too abrasive to clean it or you will destroy the close fit. I use needle nose pliers to lightly grip one side of the slot to tweak them up if they wont drop out.
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 03, 2017, 12:49:41 PM
Well, I am trying another approach....I have been unsuccesful in getting the plunger out of the carb top, so I have purchased a new carb top, plunger spring and now I am looking for the plunger.  I have seen a few online, but now sure what mine looks like seeings it is stuck inside the carb top.  Can anyone provide me with a replacement plunger part?  Even a picture of what it looks like so I can have one made.  Thank you all so much....Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: mqtsteve on September 04, 2017, 10:39:51 AM
Mike,
Have you tried gently squeezing together (with small needle nose) the gap at the top of the plunger while pulling up on it?  Sounds like the cable holding part of the plunger may have widened contacting the threads at the bottom.  Be careful not to damage the threads.  Good luck, Steve  (I can send some pics, unable to upload them)
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 05, 2017, 07:48:49 AM
Hi Steve,

   I see what you are saying now that I have seen what the plunger is supposed to look like.  Mine is missing the top nub grab onto making it very difficult to get a hold of.  I did however get it out and have ordered a new plunger.  I had already bought a new mixing chamber, so when the new plunger arrives I will re-assemble everything and hope that I can breathe some new life into this old bike!  Thank you for the pics and explaination!!  Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: BRT-GTR on September 06, 2017, 06:33:43 AM
          Mike,
                   Glad to hear you have finally got the plunger out :D , that was a toughie !  So what was jamming it ?        Good luck with getting her running when everything is back together.               Brian.
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 11, 2017, 06:12:07 PM
Hello All,

   Well, it's alive!!  After sitting for 47 years, engine itseized....It is running!  Thank you to everyone here on this forum for all of your help and direction....I don't think I could have done it without you.

 Now to dial it all in!  I am having a little trouble adjusting the clutch.  I can dry shift it through the gears, but when the bike is running I am unable to make a smooth transition.  It seems to me the gears do not disengage even when I pull the clutch in.  In the maunal it says there should be 1-1/4" between the pivot and the spring pin....my measures more around 1-9/16" but I am unable to get the distance any smaller.  I am wondering if anyone has any input for me on this one....Thank you all very much.....Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: mqtsteve on September 12, 2017, 07:03:27 AM
Mike,
Have you checked to see if the 6x10mm roller (p/n 09056-105) is in the release screw assembly?  I've had engines that were missing it.  I have a parts engine that had a small bearing in its place.  If it's missing you'll have trouble adjusting the clutch.  Glad to hear it's running.  Good luck! Steve
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 13, 2017, 05:02:50 PM
Hi Steve,

   Man are you good!!  That pin is NOT installed!  Now for the big question??  Can I instell the pin from this side or will I have to take the that whole side cover off?  Thank you again for the help!  Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: BS Mechanic on September 13, 2017, 07:13:14 PM
Good catch!

Memory says the pin can go in from either side.
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 13, 2017, 09:32:24 PM
Low and behold, I found the pin in the box I had kept my parts in...stuck under the lip of the box! Does not want to slide in from the outside...Kinda a bummer, but it could be alot worse!  If you have any other suggestions I am open to them, otherwise, I will be draining oil and removing the side cover this weekend and install the pin.  I'll keep you posted....Thanks again, Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: BS Mechanic on September 13, 2017, 09:36:26 PM
Memory's not too bad, but reading comprehension is apparently not so great!  I'm thinking 350 where I should be 90!  Apologies!
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 18, 2017, 08:02:13 AM
I pulled the clutch side the the engine off and installed the 6MM x 10MM pin....buttoned everything back up and it now shifts nice and smooth!!  Thank you to everyone for your help!!  There is such a wealth of knowledge here and you all have taught me a bunch!  Thank you!  I will post a picture or two later!  Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: stingray68 on September 19, 2017, 12:08:19 PM
I snapped a quick picture last night....1965 Trail 90 bought from original owner....1400 miles.  Had sat for 45 years with out running....piston was seized.  I had the cylinder bored, new piston, rings, nearly every bearing and oil seal replaced.  Runs and rides like a champ!  Thank you to everyone here for all of your help.....Best Regards, Mike
Title: Re: Help Disconnecting Carb From Choke BS90 Trail
Post by: old smokey on October 14, 2017, 07:40:25 PM
That's a nice looking bike to take the credit for!